Fiber-optic sensors provide remote access, are readily embedded within structures, and can operate in harsh environments. Nevertheless, fiber-optic sensing of liquids has been largely restricted to measurements of refractive index and absorption spectroscopy. The temporal dynamics of fluid evaporation have Read More …
Author: Blaž
Cost-efficient speckle interferometry with plastic optical fiber for unobtrusive monitoring of human vital signs
A cost-efficient plastic optical fiber (POF) system for unobtrusive monitoring of human vital signs is presented. The system is based on speckle interferometry. A laser diode is butt-coupled to the POF whose exit face projects speckle patterns onto a linear Read More …
Focused ion beam post-processing of optical fiber Fabry-Perot cavities for sensing applications
Focused ion beam technology is combined with chemical etching of specifically designed fibers to create Fabry-Perot interferometers. Hydrofluoric acid is used to etch special fibers and create microwires with diameters of 15 ?m. These microwires are then milled with a Read More …
Monitoring and analysis of pendant droplets evaporation using bare and monolayer-coated optical fiber facets
The monitoring of sub nano-liter pendant liquid droplets, during their evaporation from the cleaved facet of a standard optical fiber, is proposed and demonstrated. The combined reflections of incident light from the two boundaries, between fiber and liquid and between Read More …
Quasi-distributed twist/torsion sensor
This paper presents a fiber-optic quasi-distributed in-line twist/rotation sensor. The presented sensor consists of a polarization maintaining lead-in fiber and series of in-line fiber polarizers with integrated semi-reflective mirrors that are interconnected by a standard single mode fiber. Sections of Read More …
Miniature, all-fiber rotation sensor based on temperature compensated wave plate
This paper presents a miniature, all-fiber fiber optic twist/rotation sensor. The proposed sensor consists of polarization maintaining lead-in fiber (PMF), a short section of standard (fully circularly symmetric) single-mode fiber, which is exposed to twist/axial rotation, an all-fiber quarter-wave wave Read More …
In-line, fiber-optic polarimetric twist/torsion sensor
This letter presents an optical fiber twist/torsion sensor that utilizes dissimilar polarization-preserving characteristics of standard single-mode and high-birefringence fibers. When only one polarization mode of the highbirefringence fiber is excited, spatial orientation of the E-field vector follows the fiber’s principal Read More …
In-Line Fabry-Perot Refractive Index Sensor
An in-line intrinsic Fabry-Perot refractive index (RI) sensor is demonstrated. The sensor consists of a short single-mode fiber (SMF) section with removed cladding that is fusion spliced between two lead fibers containing in-fiber mirrors. The measured medium surrounding the decladed Read More …
Nanowire-based refractive index sensor on the tip of an optical fiber
This letter presents a refractive index sensor created at the tip of an optical fiber that utilizes silica nanowire within a radius of between 225 nm and 600 nm, as a sensing element. Sensitivity in excess of 800 nm/RIU was Read More …
A fiber-optic system for the quasi-distributed detection of liquids
This letter presents a multiplexed fiber-optic sensor array suitable for detection of liquid intrusions, spills, and leaks. The proposed detection systems is based on active heating and observation of temperature changes in short sections of optically absorbing (vanadium-doped) optical fibers Read More …